Dielectric ceramics/TiO₂/single-crystalline silicon nanomembrane heterostructure for high performance flexible thin-film transistors on plastic substrates

Abstract

Dielectric ceramics/TiO2/single-crystalline silicon nanomembrane heterostructure for high performance flexible thin-film transistors.

Flexible Hybrid Single-Crystalline Silicon Nanomembrane Thin-Film Transistor with Organic Polymeric Polystyrene as a Gate Dielectric on a Plastic Substrate

“…However, the dielectric layer maintained good stability at high frequency. The dielectric constant ε r of the PS layer was calculated to be ∼2.6 (approximately consistent with ref and ) according to the equation where ε 0 is the vacuum permittivity, C i is the quasi-static unit-area capacitance, and d is the thickness of the PS dielectric layer. Furthermore, the dielectric loss also remained at ∼0.04 within the range 10–10 6 Hz.…”

“…The maximum transconductance reached ∼6.5 μS at an applied gate voltage of ∼1.35 V. During the annealing process, the effective distance between the doped regions ( L ) may become slightly smaller than 4 μm (∼3.8 μm) because of ion diffusion. , Therefore, the calculated mobility taking into account the diffusion effect should be appropriate according to the equation where C ox is the quasi-static unit-area capacitance of the gate dielectric. The effective channel electron mobility was calculated to be ∼120 cm 2 V –1 S –1 , comparable to those of SiNM TFTs based on inorganic dielectrics ,, and much higher than those of TFTs based on amorphous, polycrystalline, and organic semiconductors. − ,− An ∼250 mV/dec subthreshold swing (SS) was also calculated by the equation which indicated that the TFT can operate at high speed in the subthreshold region. The interfacial trap density ( D it ) can be obtained through the equation where k is the Boltzmann constant, T is the absolute temperature, q is the unit electron charge, and C ox is the quasi-static unit-area capacitance of the gate dielectric.…”

“…The effective channel electron mobility was calculated to be ∼120 cm 2 V –1 S –1 , comparable to those of SiNM TFTs based on inorganic dielectrics ,, and much higher than those of TFTs based on amorphous, polycrystalline, and organic semiconductors. − ,− An ∼250 mV/dec subthreshold swing (SS) was also calculated by the equation which indicated that the TFT can operate at high speed in the subthreshold region. The interfacial trap density ( D it ) can be obtained through the equation where k is the Boltzmann constant, T is the absolute temperature, q is the unit electron charge, and C ox is the quasi-static unit-area capacitance of the gate dielectric. The interfacial trap density was calculated to be as low as ∼2.06 × 10 12 eV –1 cm –2 , comparable to those of SiNM TFTs fabricated with clean and smooth dielectric surfaces by using a transfer process. , The PS dielectric layer has the merits of good roughness and cleanliness because fewer impurities and suspension bonds were introduced at the SiNM/PS interface, which resulted in a low level of the interface states. , Transfer characteristic enabled dual-direction sweeping showed a low hysteresis level (Figure S1).…”

“…The interfacial trap density ( D it ) can be obtained through the equation where k is the Boltzmann constant, T is the absolute temperature, q is the unit electron charge, and C ox is the quasi-static unit-area capacitance of the gate dielectric. The interfacial trap density was calculated to be as low as ∼2.06 × 10 12 eV –1 cm –2 , comparable to those of SiNM TFTs fabricated with clean and smooth dielectric surfaces by using a transfer process. , The PS dielectric layer has the merits of good roughness and cleanliness because fewer impurities and suspension bonds were introduced at the SiNM/PS interface, which resulted in a low level of the interface states. , Transfer characteristic enabled dual-direction sweeping showed a low hysteresis level (Figure S1). This also implied a less effective interface charge of the SiNM/PS hybrid TFT, which was consistent with the calculated low interfacial trap density.…”